Robinson , Jacob2024-05-212024-052024-04-19May 2024Alrashdan, Fatima. Wireless Magnetoelectric Communication for Bioelectronics. (2024). PhD diss., Rice University. https://hdl.handle.net/1911/116144https://hdl.handle.net/1911/116144EMBARGO NOTE: This item is embargoed until 2025-05-01Implantable bioelectronics hold great potential to improve the diagnosis and treatment of myriad chronic health conditions. Wireless bioelectronic implants that continuously monitor the patient’s physiological state and transmit these data in real-time without tethers would improve diagnosis and facilitate adaptive therapeutic interventions. However, existing wireless communication modalities, such as Bluetooth, radio frequency, and ultrasound, have performance trade-offs regarding implant size, misalignment tolerance, power consumption, and operational distance. In this dissertation, I present the first wireless backscatter magnetoelectric communication system that features a miniaturized size, ultra-low power consumption, and deep operational distance with high misalignment tolerance. The system leverages two fundamental characteristics of the magnetoelectric transducers. Firstly, magnetoelectric materials generate a backscattered magnetic field when excited by an external field; we exploit these fields as a carrier signal. The magnetoelectric implant consumes negligible power for carrier generation since the external field that induces this signal is generated outside the body. Secondly, the characteristics of the backscattered field can be modulated by an external electric load; thus, we can use load modulation for digital data encoding. This design enables continuous, real-time data transmission from a mm-sized magnetoelectric. bioimplant to a custom-designed external transceiver. Our benchtop testing shows that the system can support an operational range within 55 mm while maintaining a bit error rate (BER) of less than 1E-6. Furthermore, the system is robust to translational misalignment; the system performance is maintained with a misalignment of more than 10 mm. To validate the system reliability in real-life applications and facilitate the clinical translation of this technology, we tested the system operation in a porcine model. We have shown two demonstrations of in-vivo studies: wireless monitoring of stimulation electrode impedance for cortical brain implants and real-time remote monitoring of electrical intracardiac signals for cardiac implants. The proposed technology could enable the design of next-generation bioelectronics that feature real-time physiology monitoring for more precise diagnosis, as well as closed-loop systems for personalized therapies.application/pdfengCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.BioelectronicsWireless communicationMagnetoelectriccardiacThesis2024-05-21